Method of and Apparatus for Simultaneously Providing Tone and Intermittent Link Onto a Cable to Assist Identifying the Cable

1. A test instrument for testing a cable under test, comprising: a tone driver for providing an intermittent tone to the cable under test; a link pulse generator for providing link pulses to the cable under test; wherein said tone driver and said link pulse generator simultaneously provide tone and link pulses to the cable under test.

2. A test instrument according to claim 1 , wherein said cable under test has at least a first and second wires, further comprising a swapper for swapping the link pulse between said first and second wires of the cable under test.

3. A test instrument according to claim 1 , wherein said cable comprises transmit and receive pairs, wherein said test instrument further comprises a transmit and receive swapper, for swapping said link pulse from said link pulse generator between said transmit and receive pairs.

4. A test instrument according to claim 3 , wherein said transmit and receive swapping is repeatedly performed.

5. A test instrument according to claim 1 , wherein said tone driver is adapted to provide a tone of selectable frequency.

6. A test instrument according to claim 1 , wherein said tone driver is adapted to provide a tone of varying frequency.

7. A test instrument according to claim 6 , wherein said tone is a warbling tone.

8. A test instrument according to claim 1 , further comprising: a link detector for detecting when link is present; and a link pulse timer, for timing the generation of link pulses based on the detection of link by said link detector.

9. A device for testing Ethernet network cables, comprising: a microprocessor; a tone driver for providing an intermittent tone to the cable under test; a link pulse generator for providing link pulses to the cable under test; wherein said tone driver and said link pulses generator simultaneously provide tone and link pulses to the cable under test under direction of said microprocessor.

10. A device for testing Ethernet network cables according to claim 9 , wherein said cable comprises transmit and receive pairs, wherein said test instrument further comprises a transmit and receive swapper, for swapping said link pulse from said link pulse generator between said transmit and receive pairs.

11. A device for testing Ethernet network cables according to claim 10 , wherein said swapper performs the swapping operation under timing control from said microprocessor.

12. A device for testing Ethernet network cables according to claim 11 , wherein said transmit and receive swapping is repeatedly performed.

13. A device for testing Ethernet network cables according to claim 9 , wherein said tone driver is adapted to provide a tone of selectable frequency.

14. A device for testing Ethernet network cables according to claim 9 , wherein said tone driver is adapted to provide a tone of varying frequency.

15. A device for testing Ethernet network cables according to claim 14 , wherein said tone is a warbling tone.

16. A device for testing Ethernet network cables according to claim 9 , further comprising: a link detector for detecting when link is present; and wherein said microprocessor provides a link pulse timer, for timing the generation of link pulses based on the detection of link by said link detector.

17. A method for testing a network cable, comprising: applying a tone to the network cable; and applying link pulses to the network cable, wherein said step of applying a tone to the network cable and said step of applying link pulses to the network cable are performed substantially simultaneously.

18. The method according to claim 17 , further comprising swapping the link pulse between transmit and receive wires of the cable under test.

19. The method according to claim 17 , wherein said step of applying a tone comprises applying the tone in a common mode.

20. The method according to claim 17 , further comprising the step of varying the tone frequency in accordance with a timing.